In agricultural production systems, aphid-transmitted plant viruses may cause considerable yield losses. On conventional fields, insecticides are therefore often used to control aphids. The associated negative environmental impacts can be reduced if insecticide use is reduced.The "FlowerBeet" project is investigating whether aphid infestation in sugar beets can be controlled by enhancing natural enemy population densities. Early infestation with aphids, combined with the transmission of yellows viruses, leads to considerable yield losses in sugar beet.